[Mesa-dev] [PATCH 1/5] r600g: disable CP DMA on r7xx

[Marek Olšák]

also don't require dword alignment with CP DMA for buffer transfers, which
is a leftover from the days when we used streamout to copy buffers

NOTE: This is a candidate for the 9.1 branch.
---
 src/gallium/drivers/r600/r600_blit.c       |    3 +--
 src/gallium/drivers/r600/r600_buffer.c     |    7 ++++---
 src/gallium/drivers/r600/r600_hw_context.c |    7 +------
 src/gallium/drivers/r600/r600_pipe.c       |    3 +++
 src/gallium/drivers/r600/r600_pipe.h       |    1 +
 5 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/src/gallium/drivers/r600/r600_blit.c b/src/gallium/drivers/r600/r600_blit.c
index 3e0d89c..0d879c9 100644
--- a/src/gallium/drivers/r600/r600_blit.c
+++ b/src/gallium/drivers/r600/r600_blit.c
@@ -508,8 +508,7 @@ void r600_copy_buffer(struct pipe_context *ctx, struct pipe_resource *dst, unsig
 {
 	struct r600_context *rctx = (struct r600_context*)ctx;
 
-	/* CP DMA doesn't work on R600 (flushing seems to be unreliable). */
-	if (rctx->screen->info.drm_minor >= 27 && rctx->chip_class >= R700) {
+	if (rctx->screen->has_cp_dma) {
 		r600_cp_dma_copy_buffer(rctx, dst, dstx, src, src_box->x, src_box->width);
 	}
 	else if (rctx->screen->has_streamout &&
diff --git a/src/gallium/drivers/r600/r600_buffer.c b/src/gallium/drivers/r600/r600_buffer.c
index 6df0d91..e0ac047 100644
--- a/src/gallium/drivers/r600/r600_buffer.c
+++ b/src/gallium/drivers/r600/r600_buffer.c
@@ -139,9 +139,10 @@ static void *r600_buffer_transfer_map(struct pipe_context *ctx,
 	}
 	else if ((usage & PIPE_TRANSFER_DISCARD_RANGE) &&
 		 !(usage & PIPE_TRANSFER_UNSYNCHRONIZED) &&
-		 rctx->screen->has_streamout &&
-		 /* The buffer range must be aligned to 4. */
-		 box->x % 4 == 0 && box->width % 4 == 0) {
+		 (rctx->screen->has_cp_dma ||
+		  (rctx->screen->has_streamout &&
+		   /* The buffer range must be aligned to 4 with streamout. */
+		   box->x % 4 == 0 && box->width % 4 == 0))) {
 		assert(usage & PIPE_TRANSFER_WRITE);
 
 		/* Check if mapping this buffer would cause waiting for the GPU. */
diff --git a/src/gallium/drivers/r600/r600_hw_context.c b/src/gallium/drivers/r600/r600_hw_context.c
index ec098c1..6a87abc 100644
--- a/src/gallium/drivers/r600/r600_hw_context.c
+++ b/src/gallium/drivers/r600/r600_hw_context.c
@@ -1107,12 +1107,7 @@ void r600_cp_dma_copy_buffer(struct r600_context *rctx,
 	struct radeon_winsys_cs *cs = rctx->rings.gfx.cs;
 
 	assert(size);
-	assert(rctx->chip_class != R600);
-
-	/* CP DMA doesn't work on R600 (flushing seems to be unreliable). */
-	if (rctx->chip_class == R600) {
-		return;
-	}
+	assert(rctx->screen->has_cp_dma);
 
 	dst_offset += r600_resource_va(&rctx->screen->screen, dst);
 	src_offset += r600_resource_va(&rctx->screen->screen, src);
diff --git a/src/gallium/drivers/r600/r600_pipe.c b/src/gallium/drivers/r600/r600_pipe.c
index f1019f4..e2d86e9 100644
--- a/src/gallium/drivers/r600/r600_pipe.c
+++ b/src/gallium/drivers/r600/r600_pipe.c
@@ -1111,6 +1111,9 @@ struct pipe_screen *r600_screen_create(struct radeon_winsys *ws)
 		break;
 	}
 
+	/* CP DMA doesn't work on R600-R700 (flushing seems to be unreliable). */
+	rscreen->has_cp_dma = rscreen->info.drm_minor >= 27 && rscreen->chip_class >= EVERGREEN;
+
 	if (r600_init_tiling(rscreen)) {
 		FREE(rscreen);
 		return NULL;
diff --git a/src/gallium/drivers/r600/r600_pipe.h b/src/gallium/drivers/r600/r600_pipe.h
index 88b587e..2a5457e 100644
--- a/src/gallium/drivers/r600/r600_pipe.h
+++ b/src/gallium/drivers/r600/r600_pipe.h
@@ -236,6 +236,7 @@ struct r600_screen {
 	struct radeon_info		info;
 	bool				has_streamout;
 	bool				has_msaa;
+	bool				has_cp_dma;
 	enum r600_msaa_texture_mode	msaa_texture_support;
 	bool				use_hyperz;
 	struct r600_tiling_info		tiling_info;
-- 
1.7.10.4